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Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,China:Evidence from Biomarkers,Major and Trace Elements

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 220-240页

作者： WANG Xiang LIU Guangdi SONG Zezhang SUN Mingliang WANG Xiaolin WANG Feilong CHEN Rongtao geng mingyang LI Yishu State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China China National Offshore Oil Co. Ltd.(CNOOC)Tianjin Branch CompanyTianjin 300459China CNOOC Research Institute Beijing 100028China

The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain *** address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were *** above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater ***,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and *** the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant ***,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial *** OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and *** subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct ***,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace *** established models

关键词： petroleum geology source rocks depositional environments biomarkers major elements trace elements Bozhong Sag

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连锁股东与企业财务杠杆

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未来与发展 2024年第6期48卷 62-74页

作者：耿明阳南开大学商学院天津300071

资本市场中投资人在两家同业企业中同时持股成为连锁股东。利用2011-2020年中国A股上市公司数据,本文研究了连锁股东对企业财务杠杆的影响。研究发现,连锁股东能够显著降低企业财务杠杆,在进行一系列稳健性及内生性检验后结论依然成立... 详细信息

资本市场中投资人在两家同业企业中同时持股成为连锁股东。利用2011-2020年中国A股上市公司数据,本文研究了连锁股东对企业财务杠杆的影响。研究发现,连锁股东能够显著降低企业财务杠杆,在进行一系列稳健性及内生性检验后结论依然成立。机制研究发现,连锁股东通过权益融资渠道、信息传递渠道及监督治理渠道3个渠道降低财务杠杆。异质性研究表明,连锁股东能够成为区域金融监管及市场外部监督不足时的有效补充。经济后果分析表明连锁股东推动企业降低财务杠杆能够有助于提升企业经营绩效并降低经营风险。

关键词：连锁股东财务杠杆监督效应过度负债

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监管型小股东对股价同步性的影响研究

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管理学报 2024年第2期21卷 269-277页

作者：李姝金振谢雁翔耿明阳南开大学商学院南开大学中国公司治理研究院中国财政科学研究院北京市100142

基于2016年2月中证中小投资者服务中心(简称投服中心)持股行权试点的研究场景,采用双重差分法考察投服中心对公司股价同步性的影响。研究发现:作为监管型小股东,投服中心持股行权降低了公司的股价同步性。进一步地,投服中心对股价同步... 详细信息

基于2016年2月中证中小投资者服务中心(简称投服中心)持股行权试点的研究场景,采用双重差分法考察投服中心对公司股价同步性的影响。研究发现:作为监管型小股东,投服中心持股行权降低了公司的股价同步性。进一步地,投服中心对股价同步性的影响在分析师关注度较低、媒体报道较少时更显著。机制检验显示,投服中心成立后上市公司的信息披露质量提高,管理层业绩预告质量改善,产生了信息效应;投服中心行权引起媒体和监管部门的关注,可减少大股东的利益侵占行为,提高中小股东参与股东大会的积极性,发挥出治理效应。

关键词：监管型小股东投服中心股价同步性中小投资者保护

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基于SERS的苹果树腐烂病原菌早期侵染检测

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农业工程学报 2024年第5期40卷 224-230页

作者：关洪浦耿明阳周逸博王妍许德芳赵艳茹西北农林科技大学机械与电子工程学院杨凌712100 西北农林科技大学植物保护学院杨凌712100 吕梁学院矿业工程系吕梁033001 农业农村部农业物联网重点实验室杨凌712100 陕西省农业信息感知与智能服务重点实验室杨凌712100

为了早期诊断由黑腐皮壳真菌(Valsa mali Miyabe et Yamada)引起的苹果树腐烂病,该研究基于表面增强拉曼光谱(surface-enhanced Raman scattering,SERS)技术,以腐烂病菌丝、病原菌丝侵染的苹果树和健康的苹果树枝作为研究对象,结合S-G... 详细信息

为了早期诊断由黑腐皮壳真菌(Valsa mali Miyabe et Yamada)引起的苹果树腐烂病,该研究基于表面增强拉曼光谱(surface-enhanced Raman scattering,SERS)技术,以腐烂病菌丝、病原菌丝侵染的苹果树和健康的苹果树枝作为研究对象,结合S-G平滑和迭代自适应加权惩罚最小二乘法进行拉曼光谱预处理,经解析发现病原菌丝与染菌样本在1 598、1 595 cm^(-1)和2 930、2 925 cm^(-1)附近敏感谱峰明显区别于健康样本。重复试验分析发现,病原菌侵染可致寄主特征谱峰偏移以及谱峰强度改变:健康样本在1 286 cm^(-1)附近的特征峰随病原菌的侵染偏移至1 365 cm^(-1)附近;健康样本在1 286与1 587 cm^(-1)附近的谱峰强度比值小于0.5,染菌样本在1 365与1 595 cm^(-1)附近的谱峰强度比值大于0.5,而菌丝在1 327与1 598 cm^(-1)附近的谱峰强度比值大于1.0;1 595 cm^(-1)附近谱峰强度因染病而增强。构建BP神经网络模型进行早期染病样本的快速判别,识别率达90%以上。研究表明SERS技术结合BP神经网络可以准确识别苹果树腐烂病原菌丝,从而进行苹果树枝腐烂病的早期诊断,为植物病害的早期快速诊断和病害发生预警提供了研究思路和有效手段。

关键词：病害光谱表面增强拉曼光谱(SERS) 苹果树腐烂病早期检测 BP-ANN

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全再生细骨料混凝土的制备及性能试验研究

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湖南工程学院学报（自然科学版） 2024年第1期34卷 68-75页

作者：耿明阳李小华曾智龚成湖南工程学院建筑工程学院湘潭411104 湖南工程学院绿色低碳建筑节能与材料技术湖南省工程研究中心湘潭411104

为提高再生细骨料(regenerate fine aggregates,RFA)的回收使用率,本研究采用一种含砖RFA进行全再生细骨料混凝土(fully recycled fine aggregate concrete,FRFAC)的试验制备.设计吸水率试验拟合公式计算RFA的主要组成及含量;通过设计... 详细信息

为提高再生细骨料(regenerate fine aggregates,RFA)的回收使用率,本研究采用一种含砖RFA进行全再生细骨料混凝土(fully recycled fine aggregate concrete,FRFAC)的试验制备.设计吸水率试验拟合公式计算RFA的主要组成及含量;通过设计正交试验研究水料比、减水剂和RFA粒径级配对不同养护天数下FRFAC的强度与热工性能的影响.研究结果表明,该RFA中主要包含废砖、废混凝土和泥块,其含量分别为13.58%、52.98%和33.44%,泥块含量较多,所以在制备前需对RFA进行筛分处理,该RFA平均吸水率较大,所以需采用饱和面干法进行预处理;对FRFAC强度影响最大的是RFA粒径级配,其次是水料比和减水剂,强度随着养护天数呈缓慢上升趋势;FRFAC的导热系数低,通过抗压导热交互分析得到配比最优方案为A3B3C2,制备的FRFAC强度达到25.8 MPa,导热系数为0.4636 W/(m·K),可用于建筑工程中.

关键词：建筑垃圾全再生细骨料混凝土吸水率实验正交试验

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Optically transparent graphene-based cognitive metasurface for adaptive frequency manipulation

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Photonics Research 2023年第1期11卷 129-136页

作者： mingyang geng XIAOLU YANG HAO CHEN XINZHI BO MENGZI LI ZHENGUO LIU WEIBING LU State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast UniversityNanjing 210096China Center for Flexible RF Technology Frontiers Science Center for Mobile Information Communication and SecuritySoutheast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211111China

Optically transparent microwave absorbing metasurfaces have shown great potential and are needed in multiple applications environments containing optical windows owing to their ability to reduce backscattering electromagnetic(EM)signals while keeping continuous optical ***,they are also required to have adaptive EM manipulation capability to cope with complex and capricious EM *** a general approach,distributed circuit components,including positive-intrinsic-negative diodes and varactors and sensing components,are integrated with passive absorbing metasurfaces to realize adaptive control of microwave ***,these circuit elements generally require bulky electrical wires and complex control circuits to regulate the operating state,resulting in the absorbing structures being optically ***,it is a great challenge to realize self-operating absorbers while maintaining optical ***,we report an optically transparent cognitive metasurface made of patterned graphene sandwich structures and a radio frequency detector,which can achieve adaptive frequency manipulation to match incident EM *** a proof-of-principle application example,we realize a closed-loop automatic absorber system prototype of the proposed graphene metasurface with self-adaptive frequency variation,without any human *** approach may facilitate other adaptive metadevices in microwave regime with high-level recognition and manipulation and,more generally,promote the development of intelligent stealth technologies.

关键词： transparent microwave absorber

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VAT Neutrality and Corporate Cash Holdings—Based on the Research of Uncredited VAT Refund Policy

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China Finance and Economic Review 2023年第2期12卷 49-71页

作者： Yanxiang Xie Jiaqi Qin Zhen Jin mingyang geng Nankai Business School Corporate Finance Research Center at School of Finance Nankai University

This paper regards the uncredited value-added tax(VAT)refund policy promulgated in 2018 as an exogenous shock to improve the neutrality for *** on the statistics of listed companies in the non-financial sectors from 2013 to 2020,this paper applies the difference-in-differences(DID)approach to study the impact of the uncredited VAT refund policy on corporate cash *** study finds that the policy has eased the impact of non-tax-neutral impact of non-refundable tax credits and lowered the level of corporate cash ***,the analysis of capital sources verified that the policy has optimized the corporate capital *** findings have proved to be robust after a series of *** the level of cross-sectional differences,the uncredited VAT refund policy exerts both"resource effect"and"signal effect",enabling companies to reduce cash holdings in the dimensions of both tax endowment and market *** the level of policy effects,the policy improved the corporate behavior of high cash holdings for the production and operation cycle,with more notable impact on enterprises with higher tax credit *** the level of economic consequences,the adjustment of corporate cash holdings induced by uncredited VAT refund policy has significantly improved operating performance and reduced performance volatility,with a greater impact on enterprises with high capital *** research findings evaluate the uncredited VAT refund policy from the perspective of tax neutrality,laying a theoretical foundation for further optimizing the uncredited VAT refund policy and the modern fiscal,tax and financial systems.

关键词： value-added tax(VAT) tax neutrality corporate cash holdings uncredited VAT refund policy

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建筑垃圾多孔砌块孔洞特性分析及优化模型建立

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建筑节能（中英文） 2024年第1期52卷 140-148页

作者：覃向阳李小华曾智罗伟夏凡耿明阳湖南工程学院建筑工程学院湖南湘潭411100

选取建筑垃圾作为骨料制作自密实多孔砌块,从热工和力学性能两方面分析孔洞特征的影响,确定基本孔洞特征,基于这些特征设计出6种优化模型方案,利用ANSYS有限元软件模拟模型的导热、抗压过程,以传热及受载应力云图来分析讨论,结合数值模... 详细信息

选取建筑垃圾作为骨料制作自密实多孔砌块,从热工和力学性能两方面分析孔洞特征的影响,确定基本孔洞特征,基于这些特征设计出6种优化模型方案,利用ANSYS有限元软件模拟模型的导热、抗压过程,以传热及受载应力云图来分析讨论,结合数值模拟结果进一步对比,最终确定两类优化模型。结果表明:矩形孔砌块综合性能较为优良,其各因素中孔洞率对砌块的综合性能影响程度最大,其余依次为排列方式、孔排列数、长宽比。两类砌块优化模型中,一类是热工性能良好、力学性能优异的模型1-NHB2:λ_(d)=0.1283 W/(m·K),F_(m)=12.756 MPa;另一类是力学性能稳定、热工性能突出的模型2-NHB5:λ_(d)=0.1086 W/(m·K),F_(m)=11.126 MPa。

关键词：再生多孔砌块自密实多孔砖 ANSYS模拟仿真热工性能力学性能

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Distribution characteristics and its controlling factor of lacustrine high-quality source rocks in the Bozhong sag,Bohai Bay Basin

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Petroleum Research 2019年第3期4卷 227-237页

作者： Hefeng Sun Lifang Liu Xue Jiang Shengbing Huang mingyang geng Shaoping Chen Nan Li Pu Shen CNOOC International Limited Beijing100027China CNOOC Research Institute Co.Ltd. Beijing100028China

Distribution of Paleogene lacustrine high-quality source rocks in the Bozhong sag in Bohai Bay Basin is analyzed through data of geochemistry,geology and well logging,and its differences under the control of climate and tectonics is also well *** characteristics of the high-quality source rocks developed in the saline environment controlled by the climate are quite different from that developed in the rapid subsidence environment controlled by *** high-quality source rocks in Member 1 of Shahejie Formation developed in the saline environment account for 81.9%of total subsag area,and are distributed widely and *** high-quality source rocks in Member 3 of Shahejie Formation and Member 3 of Dongying Formation is developed in the tectonic subsidence environment,and horizontally,the subsag subsidence rates has a positive correlation with the area proportion of the high-quality source rocks in the sag;vertically,the reduction-oxidation interface of the lake controls the enrichment of highquality source *** by the saline environment and rapid subsidence environment,the highquality source rocks in the Bozhong sag and adjacent areas have three types of development condition:the saline water,the tectonic subsidence,and joint control of the saline water and the tectonic *** humid climate and low subsidence rate are not favorable for development of high-quality source rocks.

关键词： Lacustrine high-quality source rocks Saline environment Rapid subsidence Reduction-oxidation interface Bozhong sag Bohai Bay Basin

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Mixed Dead-time Effect Suppression Strategy for Modular Multilevel Converters

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1075-1084页

作者： Zhi geng Minxiao Han School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 102206China IEEE

Dead time is necessary for the coupled power switches to prevent shoot-through,especially in the modular multilevel converters(MMCs)with a large number of power *** paper proposes a dead-time effect suppression strategy for MMCs with nearest level *** operational principles of MMCs are first *** to the operational features of MMCs,the method that removes a switching signal from the coupled switches and the reduced switching frequency voltage balancing algorithms(RSFVBAs)are mixed in the proposed *** the intervals that are furthest away from the zerocrossing points(ZCP)of arm currents,the single switching signal method can completely eliminate the dead-time effect(DTE).Alternatively,the DTE is suppressed by the RSFVBA in intervals that are close to the *** the combination of the two methods,the dependence of the DTE suppression method on currents is reduced and the influences of ZCP are also released without degrading the normal operation performance of ***,the output performance of MMCs is improved and the voltage stress on the arm inductor dramatically ***,the validation of the method is verified by the simulation results with the professional tool Matlab/Simulink.

关键词： Dead-time effect modular multilevel converters switching frequency voltage balancing algorithm

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